Extjs checkbox selection issue

Extjs checkbox selection issue

i am working in extjs4. i have grid with checkbox selection model. Grid is
displaying files and folders. If folder get selected then i want to hide
some menu. So have written code as-
selectionchange:function( model, selected, eOpts ){
var centralPanel = me.up();
var actionBtn =
centralPanel.queryById('libraryactionBtn');
if(selected.length > 1) {
actionBtn.show();
//var i=0;
for(i=0;i<selected.length;i++)
{
if(selected[i].data.isLeaf)
{
centralPanel.queryById('library-action-menu-view').hide();
centralPanel.queryById('library-action-menu-viewOrAddTag').hide();
centralPanel.queryById('library-action-menu-viewOrAddNotes').hide();
centralPanel.queryById('library-action-menu-copyToCompaign').hide();
centralPanel.queryById('library-action-menu-copyToProject').hide();
centralPanel.queryById('library-action-menu-sendLink').hide();
centralPanel.queryById('library-action-menu-addtofavorite').hide();
centralPanel.queryById('library-action-menu-downloadItem').hide();
}
}
} else {
actionBtn.hide();
}
where selected.data.isLeaf is false for folder. Its executing correctly
only first time. Next time when i am selecting file,then also its hiding
menu for file. And if folder is deselected then also its hiding menu. So
what modifications i need to do